.zan-col {
  float: left;
  box-sizing: border-box;
  width: 0;
}

@for $i from 1 to 24 {
  .zan-col-#{$i} { width: $i * 100% / 24; }
  .zan-col-offset-#{$i} { margin-left: $i * 100% / 24; }
}
